Garmin Forerunner 405CX review

UPDATE: This model has been discontinued. For information on current models, check out our GPS for runners page.

The Garmin Forerunner 405CX updates the Forerunner 405, increasing accuracy in heart rate-based calorie computation. Using algorithms developed by exercise scientists and world-class athletes, the Forerunner 405CX monitors the micro changes in a user’s heart rate and uses that detailed information to better calculate the number of calories burned during aerobic activity.

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Another new thing — the 405CX comes with two additional form-fitting bands to accommodate large or small wrists. Like the Forerunner 405, the 405CX brings features not found on the earlier Forerunner 205 and 305 models:

For one thing, the style has changed, with a sleeker and more watch-like appearance.

A wireless connection, using ANT+Sport technology, sends data to your computer. No more cables!

The touch-sensitive bezel minimizes the need for buttons on the unit.

The map screen found on previous Forerunners is gone (it was pretty rudimentary anyway, showing only waypoints and tracks). But hey, who are we kidding? The Forerunner 405 is a runner’s training partner, not a navigation device.

Yes. I have the original 405 and it doesn’t matter how you get there, it will track you very accurately as long as it can receive from many satellites. If you’re running or biking along buildings that block the satellites, then there can be a slight problem.

I miss the mapping ability. True, many runners may not need it, but in our running club we are experiencing many who are trying new things, adventure racing, orienteering, etc, yet still run 20-30 races per year, a one-sized fits all GPS watch would be nice!

I have a MS Band 2. It’s one of few out there that has GPS built into it. You don’t need to bring your phone on a run or bike ride. It tracks heart rate. It seems to be very accurate with regard to calorie burn. The MS Health dashboard (browser app) has everything you need with summaries and details of all of your activities. Being able to see all of the stats laid out in front of you and your numbers over time can be very motivating. I’m always trying to beat my fastest time or greatest distance.

The only things I’d like to see if they ever came out with a Band 3 is the ability to store music on it and Bluetooth to some fitness headphones. Further, I’d like it to be fully water-resistant and incorporate swimming workouts/activities. Also, I’ve found through almost five months of wearing it, the band holds up well, but the contacts you connect the charger to are prone to corrosion from your sweat. Even if you wipe the thing down or clean it really well where the charging contacts are, it still develops corrosion under the seal by the contacts. This results in the contacts not always matching up with the charger. This became